Overall objective of the total project is the investigation of the afferent and efferent mechanisms inter-relating cardiovascular and sensorimotor systems. Parallel studies are carried out in normal human subjects and in acute cat preparations, with emphasis on variations in physiological (e.g. baroreceptor discharge patterns) and behavioral (e.g. signal detection or reaction time) activity, both as a function of cardiac and respiratory phase, and of patterns of heart rate change.